Fry the onion in 2 tablespoons butter until tender and mix it with the minced meat, the trimmed dried bread, milk, salt, pepper and egg. Mould the mixture in small balls of approximately 5 cm diameter. In a large frying pan fry the meat balls in butter or olive oil. Pour the wine on top of the meat balls and leave it to warm up for few minutes. Serve them warm. This recipe is for 36 pieces for a starter.